xref: /netbsd-src/usr.bin/stat/stat.c (revision 53b02e147d4ed531c0d2a5ca9b3e8026ba3e99b5)
1 /*	$NetBSD: stat.c,v 1.47 2021/08/27 18:11:07 rillig Exp $ */
2 
3 /*
4  * Copyright (c) 2002-2011 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Andrew Brown.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #if HAVE_NBTOOL_CONFIG_H
33 #include "nbtool_config.h"
34 /* config checked libc, we need the prototype as well */
35 #undef HAVE_DEVNAME
36 #endif
37 
38 #include <sys/cdefs.h>
39 #if !defined(lint)
40 __RCSID("$NetBSD: stat.c,v 1.47 2021/08/27 18:11:07 rillig Exp $");
41 #endif
42 
43 #if ! HAVE_NBTOOL_CONFIG_H
44 #define HAVE_STRUCT_STAT_ST_FLAGS 1
45 #define HAVE_STRUCT_STAT_ST_GEN 1
46 #define HAVE_STRUCT_STAT_ST_BIRTHTIME 1
47 #define HAVE_STRUCT_STAT_ST_BIRTHTIMENSEC 1
48 #define HAVE_STRUCT_STAT_ST_MTIMENSEC 1
49 #define HAVE_DEVNAME 1
50 #endif /* HAVE_NBTOOL_CONFIG_H */
51 
52 #include <sys/types.h>
53 #include <sys/stat.h>
54 
55 #include <ctype.h>
56 #include <err.h>
57 #include <errno.h>
58 #include <grp.h>
59 #include <limits.h>
60 #include <pwd.h>
61 #include <stdio.h>
62 #include <stdlib.h>
63 #include <string.h>
64 #include <time.h>
65 #include <unistd.h>
66 #include <vis.h>
67 
68 #if HAVE_STRUCT_STAT_ST_FLAGS
69 #define DEF_F "%#Xf "
70 #define RAW_F "%f "
71 #define SHELL_F " st_flags=%f"
72 #else /* HAVE_STRUCT_STAT_ST_FLAGS */
73 #define DEF_F
74 #define RAW_F
75 #define SHELL_F
76 #endif /* HAVE_STRUCT_STAT_ST_FLAGS */
77 
78 #if HAVE_STRUCT_STAT_ST_BIRTHTIME
79 #define DEF_B "\"%SB\" "
80 #define RAW_B "%B "
81 #define SHELL_B "st_birthtime=%SB "
82 #define LINUX_B	"%n Birth: %SB"
83 #else /* HAVE_STRUCT_STAT_ST_BIRTHTIME */
84 #define DEF_B
85 #define RAW_B
86 #define SHELL_B
87 #define LINUX_B
88 #endif /* HAVE_STRUCT_STAT_ST_BIRTHTIME */
89 
90 #if HAVE_STRUCT_STAT_ST_ATIM
91 #define st_atimespec st_atim
92 #define st_ctimespec st_ctim
93 #define st_mtimespec st_mtim
94 #endif /* HAVE_STRUCT_STAT_ST_ATIM */
95 
96 #define DEF_FORMAT \
97 	"%d %i %Sp %l %Su %Sg %r %z \"%Sa\" \"%Sm\" \"%Sc\" " DEF_B \
98 	"%k %b " DEF_F "%N"
99 #define RAW_FORMAT	"%d %i %#p %l %u %g %r %z %a %m %c " RAW_B \
100 	"%k %b " RAW_F "%N"
101 #define LS_FORMAT	"%Sp %l %Su %Sg %Z %Sm %N%SY"
102 #define LSF_FORMAT	"%Sp %l %Su %Sg %Z %Sm %N%T%SY"
103 #define SHELL_FORMAT \
104 	"st_dev=%d st_ino=%i st_mode=%#p st_nlink=%l " \
105 	"st_uid=%u st_gid=%g st_rdev=%r st_size=%z " \
106 	"st_atime=%Sa st_mtime=%Sm st_ctime=%Sc " SHELL_B \
107 	"st_blksize=%k st_blocks=%b" SHELL_F
108 #define LINUX_FORMAT \
109 	"  File: \"%N\"%n" \
110 	"  Size: %-11z  Blocks: %-11b  IO Block: %-11k  %HT%n" \
111 	"Device: %Hd,%Ld   Inode: %i    Links: %l%n" \
112 	"  Mode: (%Mp%03OLp/%.10Sp)         Uid: (%5u/%8Su)  Gid: (%5g/%8Sg)%n" \
113 	"Access: %Sa%n" \
114 	"Modify: %Sm%n" \
115 	"Change: %Sc" \
116 	LINUX_B
117 
118 #define TIME_FORMAT	"%b %e %T %Y"
119 
120 #define FLAG_POUND	0x01
121 #define FLAG_SPACE	0x02
122 #define FLAG_PLUS	0x04
123 #define FLAG_ZERO	0x08
124 #define FLAG_MINUS	0x10
125 
126 /*
127  * These format characters must all be unique, except the magic one.
128  */
129 #define FMT_MAGIC	'%'
130 #define FMT_DOT		'.'
131 
132 #define SIMPLE_NEWLINE	'n'
133 #define SIMPLE_TAB	't'
134 #define SIMPLE_PERCENT	'%'
135 #define SIMPLE_NUMBER	'@'
136 
137 #define FMT_POUND	'#'
138 #define FMT_SPACE	' '
139 #define FMT_PLUS	'+'
140 #define FMT_ZERO	'0'
141 #define FMT_MINUS	'-'
142 
143 #define FMT_DECIMAL 	'D'
144 #define FMT_OCTAL 	'O'
145 #define FMT_UNSIGNED 	'U'
146 #define FMT_HEX 	'X'
147 #define FMT_FLOAT 	'F'
148 #define FMT_STRING 	'S'
149 
150 #define FMTF_DECIMAL	0x01
151 #define FMTF_OCTAL	0x02
152 #define FMTF_UNSIGNED	0x04
153 #define FMTF_HEX	0x08
154 #define FMTF_FLOAT	0x10
155 #define FMTF_STRING	0x20
156 
157 #define HIGH_PIECE	'H'
158 #define MIDDLE_PIECE	'M'
159 #define LOW_PIECE	'L'
160 
161 #define	SHOW_realpath	'R'
162 #define SHOW_st_dev	'd'
163 #define SHOW_st_ino	'i'
164 #define SHOW_st_mode	'p'
165 #define SHOW_st_nlink	'l'
166 #define SHOW_st_uid	'u'
167 #define SHOW_st_gid	'g'
168 #define SHOW_st_rdev	'r'
169 #define SHOW_st_atime	'a'
170 #define SHOW_st_mtime	'm'
171 #define SHOW_st_ctime	'c'
172 #define SHOW_st_btime	'B'
173 #define SHOW_st_size	'z'
174 #define SHOW_st_blocks	'b'
175 #define SHOW_st_blksize	'k'
176 #define SHOW_st_flags	'f'
177 #define SHOW_st_gen	'v'
178 #define SHOW_symlink	'Y'
179 #define SHOW_filetype	'T'
180 #define SHOW_filename	'N'
181 #define SHOW_sizerdev	'Z'
182 
183 static void	usage(const char *) __dead;
184 static void	output(const struct stat *, const char *,
185 	    const char *, int, int, int);
186 static int	format1(const struct stat *,	/* stat info */
187 	    const char *,		/* the file name */
188 	    const char *, int,		/* the format string itself */
189 	    char *, size_t,		/* a place to put the output */
190 	    int, int, int, int,		/* the parsed format */
191 	    int, int, int);
192 
193 static const char *timefmt;
194 static int linkfail;
195 
196 #define addchar(s, c, nl) \
197 	do { \
198 		(void)fputc((c), (s)); \
199 		(*nl) = ((c) == '\n'); \
200 	} while (0/*CONSTCOND*/)
201 
202 int
203 main(int argc, char *argv[])
204 {
205 	struct stat st;
206 	int ch, rc, errs, am_readlink;
207 	int lsF, fmtchar, usestat, fn, nonl, quiet;
208 	const char *statfmt, *options, *synopsis;
209 
210 	am_readlink = 0;
211 	lsF = 0;
212 	fmtchar = '\0';
213 	usestat = 0;
214 	nonl = 0;
215 	quiet = 0;
216 	linkfail = 0;
217 	statfmt = NULL;
218 	timefmt = NULL;
219 
220 	setprogname(argv[0]);
221 
222 	if (strcmp(getprogname(), "readlink") == 0) {
223 		am_readlink = 1;
224 		options = "fnqsv";
225 		synopsis = "[-fnqsv] [file ...]";
226 		statfmt = "%Y";
227 		fmtchar = 'f';
228 		quiet = 1;
229 	} else {
230 		options = "f:FlLnqrst:x";
231 		synopsis = "[-FlLnqrsx] [-f format] [-t timefmt] [file ...]";
232 	}
233 
234 	while ((ch = getopt(argc, argv, options)) != -1)
235 		switch (ch) {
236 		case 'F':
237 			lsF = 1;
238 			break;
239 		case 'L':
240 			usestat = 1;
241 			break;
242 		case 'n':
243 			nonl = 1;
244 			break;
245 		case 'q':
246 			quiet = 1;
247 			break;
248 		case 'f':
249 			if (am_readlink) {
250 				statfmt = "%R";
251 				break;
252 			}
253 			statfmt = optarg;
254 			/* FALLTHROUGH */
255 		case 'l':
256 		case 'r':
257 		case 's':
258 			if (am_readlink) {
259 				quiet = 1;
260 				break;
261 			}
262 			/*FALLTHROUGH*/
263 		case 'x':
264 			if (fmtchar != 0)
265 				errx(1, "can't use format '%c' with '%c'",
266 				    fmtchar, ch);
267 			fmtchar = ch;
268 			break;
269 		case 't':
270 			timefmt = optarg;
271 			break;
272 		case 'v':
273 			quiet = 0;
274 			break;
275 		default:
276 			usage(synopsis);
277 		}
278 
279 	argc -= optind;
280 	argv += optind;
281 	fn = 1;
282 
283 	if (fmtchar == '\0') {
284 		if (lsF)
285 			fmtchar = 'l';
286 		else {
287 			fmtchar = 'f';
288 			statfmt = DEF_FORMAT;
289 		}
290 	}
291 
292 	if (lsF && fmtchar != 'l')
293 		errx(1, "can't use format '%c' with -F", fmtchar);
294 
295 	switch (fmtchar) {
296 	case 'f':
297 		/* statfmt already set */
298 		break;
299 	case 'l':
300 		statfmt = lsF ? LSF_FORMAT : LS_FORMAT;
301 		break;
302 	case 'r':
303 		statfmt = RAW_FORMAT;
304 		break;
305 	case 's':
306 		statfmt = SHELL_FORMAT;
307 		if (timefmt == NULL)
308 			timefmt = "%s";
309 		break;
310 	case 'x':
311 		statfmt = LINUX_FORMAT;
312 		if (timefmt == NULL)
313 			timefmt = "%Y-%m-%d %H:%M:%S.%f %z";
314 		break;
315 	default:
316 		usage(synopsis);
317 		/*NOTREACHED*/
318 	}
319 
320 	if (timefmt == NULL)
321 		timefmt = TIME_FORMAT;
322 
323 	errs = 0;
324 	do {
325 		if (argc == 0)
326 			rc = fstat(STDIN_FILENO, &st);
327 		else if (usestat) {
328 			/*
329 			 * Try stat() and if it fails, fall back to
330 			 * lstat() just in case we're examining a
331 			 * broken symlink.
332 			 */
333 			if ((rc = stat(argv[0], &st)) == -1 &&
334 			    errno == ENOENT &&
335 			    (rc = lstat(argv[0], &st)) == -1)
336 				errno = ENOENT;
337 		}
338 		else
339 			rc = lstat(argv[0], &st);
340 
341 		if (rc == -1) {
342 			errs = 1;
343 			linkfail = 1;
344 			if (!quiet)
345 				warn("%s: %s",
346 				    argc == 0 ? "(stdin)" : argv[0],
347 				    usestat ? "stat" : "lstat");
348 		}
349 		else
350 			output(&st, argv[0], statfmt, fn, nonl, quiet);
351 
352 		argv++;
353 		argc--;
354 		fn++;
355 	} while (argc > 0);
356 
357 	return (am_readlink ? linkfail : errs);
358 }
359 
360 static void
361 usage(const char *synopsis)
362 {
363 
364 	(void)fprintf(stderr, "usage: %s %s\n", getprogname(), synopsis);
365 	exit(1);
366 }
367 
368 /*
369  * Parses a format string.
370  */
371 static void
372 output(const struct stat *st, const char *file,
373     const char *statfmt, int fn, int nonl, int quiet)
374 {
375 	int flags, size, prec, ofmt, hilo, what;
376 	/*
377 	 * buf size is enough for an item of length PATH_MAX,
378 	 * multiplied by 4 for vis encoding, plus 4 for symlink
379 	 * " -> " prefix, plus 1 for \0 terminator.
380 	 */
381 	char buf[PATH_MAX * 4 + 4 + 1];
382 	const char *subfmt;
383 	int nl, t, i;
384 
385 	nl = 1;
386 	while (*statfmt != '\0') {
387 
388 		/*
389 		 * Non-format characters go straight out.
390 		 */
391 		if (*statfmt != FMT_MAGIC) {
392 			addchar(stdout, *statfmt, &nl);
393 			statfmt++;
394 			continue;
395 		}
396 
397 		/*
398 		 * The current format "substring" starts here,
399 		 * and then we skip the magic.
400 		 */
401 		subfmt = statfmt;
402 		statfmt++;
403 
404 		/*
405 		 * Some simple one-character "formats".
406 		 */
407 		switch (*statfmt) {
408 		case SIMPLE_NEWLINE:
409 			addchar(stdout, '\n', &nl);
410 			statfmt++;
411 			continue;
412 		case SIMPLE_TAB:
413 			addchar(stdout, '\t', &nl);
414 			statfmt++;
415 			continue;
416 		case SIMPLE_PERCENT:
417 			addchar(stdout, '%', &nl);
418 			statfmt++;
419 			continue;
420 		case SIMPLE_NUMBER: {
421 			char num[12], *p;
422 
423 			snprintf(num, sizeof(num), "%d", fn);
424 			for (p = &num[0]; *p; p++)
425 				addchar(stdout, *p, &nl);
426 			statfmt++;
427 			continue;
428 		}
429 		}
430 
431 		/*
432 		 * This must be an actual format string.  Format strings are
433 		 * similar to printf(3) formats up to a point, and are of
434 		 * the form:
435 		 *
436 		 *	%	required start of format
437 		 *	[-# +0]	opt. format characters
438 		 *	size	opt. field width
439 		 *	.	opt. decimal separator, followed by
440 		 *	prec	opt. precision
441 		 *	fmt	opt. output specifier (string, numeric, etc.)
442 		 *	sub	opt. sub field specifier (high, middle, low)
443 		 *	datum	required field specifier (size, mode, etc)
444 		 *
445 		 * Only the % and the datum selector are required.  All data
446 		 * have reasonable default output forms.  The "sub" specifier
447 		 * only applies to certain data (mode, dev, rdev, filetype).
448 		 * The symlink output defaults to STRING, yet will only emit
449 		 * the leading " -> " if STRING is explicitly specified.  The
450 		 * sizerdev datum will generate rdev output for character or
451 		 * block devices, and size output for all others.
452 		 * For STRING output, the # format requests vis encoding.
453 		 */
454 		flags = 0;
455 		do {
456 			if      (*statfmt == FMT_POUND)
457 				flags |= FLAG_POUND;
458 			else if (*statfmt == FMT_SPACE)
459 				flags |= FLAG_SPACE;
460 			else if (*statfmt == FMT_PLUS)
461 				flags |= FLAG_PLUS;
462 			else if (*statfmt == FMT_ZERO)
463 				flags |= FLAG_ZERO;
464 			else if (*statfmt == FMT_MINUS)
465 				flags |= FLAG_MINUS;
466 			else
467 				break;
468 			statfmt++;
469 		} while (1/*CONSTCOND*/);
470 
471 		size = -1;
472 		if (isdigit((unsigned char)*statfmt)) {
473 			size = 0;
474 			while (isdigit((unsigned char)*statfmt)) {
475 				size = (size * 10) + (*statfmt - '0');
476 				statfmt++;
477 				if (size < 0)
478 					goto badfmt;
479 			}
480 		}
481 
482 		prec = -1;
483 		if (*statfmt == FMT_DOT) {
484 			statfmt++;
485 
486 			prec = 0;
487 			while (isdigit((unsigned char)*statfmt)) {
488 				prec = (prec * 10) + (*statfmt - '0');
489 				statfmt++;
490 				if (prec < 0)
491 					goto badfmt;
492 			}
493 		}
494 
495 #define fmtcase(x, y)		case (y): (x) = (y); statfmt++; break
496 #define fmtcasef(x, y, z)	case (y): (x) = (z); statfmt++; break
497 		switch (*statfmt) {
498 			fmtcasef(ofmt, FMT_DECIMAL,	FMTF_DECIMAL);
499 			fmtcasef(ofmt, FMT_OCTAL,	FMTF_OCTAL);
500 			fmtcasef(ofmt, FMT_UNSIGNED,	FMTF_UNSIGNED);
501 			fmtcasef(ofmt, FMT_HEX,		FMTF_HEX);
502 			fmtcasef(ofmt, FMT_FLOAT,	FMTF_FLOAT);
503 			fmtcasef(ofmt, FMT_STRING,	FMTF_STRING);
504 		default:
505 			ofmt = 0;
506 			break;
507 		}
508 
509 		switch (*statfmt) {
510 			fmtcase(hilo, HIGH_PIECE);
511 			fmtcase(hilo, MIDDLE_PIECE);
512 			fmtcase(hilo, LOW_PIECE);
513 		default:
514 			hilo = 0;
515 			break;
516 		}
517 
518 		switch (*statfmt) {
519 			fmtcase(what, SHOW_realpath);
520 			fmtcase(what, SHOW_st_dev);
521 			fmtcase(what, SHOW_st_ino);
522 			fmtcase(what, SHOW_st_mode);
523 			fmtcase(what, SHOW_st_nlink);
524 			fmtcase(what, SHOW_st_uid);
525 			fmtcase(what, SHOW_st_gid);
526 			fmtcase(what, SHOW_st_rdev);
527 			fmtcase(what, SHOW_st_atime);
528 			fmtcase(what, SHOW_st_mtime);
529 			fmtcase(what, SHOW_st_ctime);
530 			fmtcase(what, SHOW_st_btime);
531 			fmtcase(what, SHOW_st_size);
532 			fmtcase(what, SHOW_st_blocks);
533 			fmtcase(what, SHOW_st_blksize);
534 			fmtcase(what, SHOW_st_flags);
535 			fmtcase(what, SHOW_st_gen);
536 			fmtcase(what, SHOW_symlink);
537 			fmtcase(what, SHOW_filetype);
538 			fmtcase(what, SHOW_filename);
539 			fmtcase(what, SHOW_sizerdev);
540 		default:
541 			goto badfmt;
542 		}
543 #undef fmtcasef
544 #undef fmtcase
545 
546 		t = format1(st,
547 		     file,
548 		     subfmt, statfmt - subfmt,
549 		     buf, sizeof(buf),
550 		     flags, size, prec, ofmt, hilo, what, quiet);
551 
552 		for (i = 0; i < t && i < (int)(sizeof(buf) - 1); i++)
553 			addchar(stdout, buf[i], &nl);
554 
555 		continue;
556 
557 	badfmt:
558 		errx(1, "%.*s: bad format",
559 		    (int)(statfmt - subfmt + 1), subfmt);
560 	}
561 
562 	if (!nl && !nonl)
563 		(void)fputc('\n', stdout);
564 	(void)fflush(stdout);
565 }
566 
567 static const char *
568 fmttime(char *buf, size_t len, const char *fmt, time_t secs, long nsecs)
569 {
570 	struct tm tm;
571 	const char *fpb, *fp1, *fp2;	/* pointers into fmt */
572 	char *fmt2 = NULL;		/* replacement fmt (if not NULL) */
573 				/* XXX init of next twp for stupid gcc only */
574 	char *f2p = NULL;		/* ptr into fmt2 - last added */
575 	size_t flen = 0;
576 	size_t o;
577 	int sl;
578 
579 	if (localtime_r(&secs, &tm) == NULL) {
580 		secs = 0;
581 		(void)localtime_r(&secs, &tm);
582 	}
583 	for (fp1 = fpb = fmt; (fp2 = strchr(fp1, '%')) != NULL; ) {
584 		if (fp2[1] != 'f') {
585 			/* make sure we don't find the 2nd '%' in "%%" */
586 			fp1 = fp2 + 1 + (fp2[1] != '\0');
587 			continue;
588 		}
589 		if (fmt2 == NULL) {
590 			/* allow for ~100 %f's in the format ... */
591 			flen = strlen(fmt) + 1024;
592 
593 			if ((fmt2 = calloc(flen, 1)) == NULL) {
594 				fp1 = fp2 + 2;
595 				continue;
596 			}
597 			f2p = fmt2;
598 
599 			o = (size_t)(fp2 - fpb);
600 			memcpy(f2p, fpb, o);	/* must fit */
601 			fmt = fmt2;
602 		} else {
603 			o = (size_t)(fp2 - fpb);
604 			if (flen > o)
605 				memcpy(f2p, fpb, o);
606 		}
607 		if (flen < o + 10) {	/* 9 digits + \0 == 10 */
608 			*f2p = '\0';
609 			break;
610 		}
611 		f2p += o;
612 		flen -= o;
613 		sl = snprintf(f2p, flen, "%.9ld", nsecs);
614 		if (sl == -1)
615 			sl = 0;
616 		f2p += sl;
617 		*f2p = '\0';
618 		flen -= sl;
619 		fp1 = fp2 + 2;
620 		fpb = fp1;
621 	}
622 	if (fmt2 != NULL) {
623 		o = strlen(fpb);
624 		if (flen > o) {
625 			memcpy(f2p, fpb, o);
626 			f2p[o] = '\0';
627 		}
628 	}
629 
630 	(void)strftime(buf, len, fmt, &tm);
631 	free(fmt2);
632 	return buf;
633 }
634 
635 /*
636  * Arranges output according to a single parsed format substring.
637  */
638 static int
639 format1(const struct stat *st,
640     const char *file,
641     const char *fmt, int flen,
642     char *buf, size_t blen,
643     int flags, int size, int prec, int ofmt,
644     int hilo, int what, int quiet)
645 {
646 	uint64_t data;
647 	char *stmp, lfmt[24], tmp[20];
648 	const char *sdata;
649 	char smode[12], sid[13], path[PATH_MAX + 4], visbuf[PATH_MAX * 4 + 4];
650 	struct passwd *pw;
651 	struct group *gr;
652 	time_t secs;
653 	long nsecs;
654 	int l;
655 	int formats;	/* bitmap of allowed formats for this datum */
656 	int small;	/* true if datum is a small integer */
657 	int gottime;	/* true if secs and nsecs are valid */
658 	int shift;	/* powers of 2 to scale numbers before printing */
659 	size_t prefixlen; /* length of constant prefix for string data */
660 
661 	formats = 0;
662 	small = 0;
663 	gottime = 0;
664 	secs = 0;
665 	nsecs = 0;
666 	shift = 0;
667 	prefixlen = 0;
668 
669 	/*
670 	 * First, pick out the data and tweak it based on hilo or
671 	 * specified output format (symlink output only).
672 	 */
673 	switch (what) {
674 	case SHOW_st_dev:
675 	case SHOW_st_rdev:
676 		small = (sizeof(st->st_dev) == 4);
677 		data = (what == SHOW_st_dev) ? st->st_dev : st->st_rdev;
678 #if HAVE_DEVNAME
679 		sdata = (what == SHOW_st_dev) ?
680 		    devname(st->st_dev, S_IFBLK) :
681 		    devname(st->st_rdev,
682 			S_ISCHR(st->st_mode) ? S_IFCHR :
683 			S_ISBLK(st->st_mode) ? S_IFBLK :
684 			0U);
685 		if (sdata == NULL)
686 			sdata = "???";
687 #endif /* HAVE_DEVNAME */
688 		if (hilo == HIGH_PIECE) {
689 			data = major(data);
690 			hilo = 0;
691 		}
692 		else if (hilo == LOW_PIECE) {
693 			data = minor((unsigned)data);
694 			hilo = 0;
695 		}
696 		formats = FMTF_DECIMAL | FMTF_OCTAL | FMTF_UNSIGNED | FMTF_HEX |
697 #if HAVE_DEVNAME
698 		    FMTF_STRING;
699 #else /* HAVE_DEVNAME */
700 		    0;
701 #endif /* HAVE_DEVNAME */
702 		if (ofmt == 0) {
703 			if (data == (uint64_t)-1)
704 				ofmt = FMTF_DECIMAL;
705 			else
706 				ofmt = FMTF_UNSIGNED;
707 		}
708 		break;
709 	case SHOW_st_ino:
710 		small = (sizeof(st->st_ino) == 4);
711 		data = st->st_ino;
712 		sdata = NULL;
713 		formats = FMTF_DECIMAL | FMTF_OCTAL | FMTF_UNSIGNED | FMTF_HEX;
714 		if (ofmt == 0)
715 			ofmt = FMTF_UNSIGNED;
716 		break;
717 	case SHOW_st_mode:
718 		small = (sizeof(st->st_mode) == 4);
719 		data = st->st_mode;
720 		strmode(st->st_mode, smode);
721 		stmp = smode;
722 		l = strlen(stmp);
723 		if (stmp[l - 1] == ' ')
724 			stmp[--l] = '\0';
725 		if (hilo == HIGH_PIECE) {
726 			data >>= 12;
727 			stmp += 1;
728 			stmp[3] = '\0';
729 			hilo = 0;
730 		}
731 		else if (hilo == MIDDLE_PIECE) {
732 			data = (data >> 9) & 07;
733 			stmp += 4;
734 			stmp[3] = '\0';
735 			hilo = 0;
736 		}
737 		else if (hilo == LOW_PIECE) {
738 			data &= 0777;
739 			stmp += 7;
740 			stmp[3] = '\0';
741 			hilo = 0;
742 		}
743 		sdata = stmp;
744 		formats = FMTF_DECIMAL | FMTF_OCTAL | FMTF_UNSIGNED | FMTF_HEX |
745 		    FMTF_STRING;
746 		if (ofmt == 0)
747 			ofmt = FMTF_OCTAL;
748 		break;
749 	case SHOW_st_nlink:
750 		small = (sizeof(st->st_dev) == 4);
751 		data = st->st_nlink;
752 		sdata = NULL;
753 		formats = FMTF_DECIMAL | FMTF_OCTAL | FMTF_UNSIGNED | FMTF_HEX;
754 		if (ofmt == 0)
755 			ofmt = FMTF_UNSIGNED;
756 		break;
757 	case SHOW_st_uid:
758 		small = (sizeof(st->st_uid) == 4);
759 		data = st->st_uid;
760 		if ((pw = getpwuid(st->st_uid)) != NULL)
761 			sdata = pw->pw_name;
762 		else {
763 			snprintf(sid, sizeof(sid), "(%ld)", (long)st->st_uid);
764 			sdata = sid;
765 		}
766 		formats = FMTF_DECIMAL | FMTF_OCTAL | FMTF_UNSIGNED | FMTF_HEX |
767 		    FMTF_STRING;
768 		if (ofmt == 0)
769 			ofmt = FMTF_UNSIGNED;
770 		break;
771 	case SHOW_st_gid:
772 		small = (sizeof(st->st_gid) == 4);
773 		data = st->st_gid;
774 		if ((gr = getgrgid(st->st_gid)) != NULL)
775 			sdata = gr->gr_name;
776 		else {
777 			snprintf(sid, sizeof(sid), "(%ld)", (long)st->st_gid);
778 			sdata = sid;
779 		}
780 		formats = FMTF_DECIMAL | FMTF_OCTAL | FMTF_UNSIGNED | FMTF_HEX |
781 		    FMTF_STRING;
782 		if (ofmt == 0)
783 			ofmt = FMTF_UNSIGNED;
784 		break;
785 	case SHOW_st_atime:
786 		gottime = 1;
787 		secs = st->st_atime;
788 #if HAVE_STRUCT_STAT_ST_MTIMENSEC
789 		nsecs = st->st_atimensec;
790 #endif
791 		/* FALLTHROUGH */
792 	case SHOW_st_mtime:
793 		if (!gottime) {
794 			gottime = 1;
795 			secs = st->st_mtime;
796 #if HAVE_STRUCT_STAT_ST_MTIMENSEC
797 			nsecs = st->st_mtimensec;
798 #endif
799 		}
800 		/* FALLTHROUGH */
801 	case SHOW_st_ctime:
802 		if (!gottime) {
803 			gottime = 1;
804 			secs = st->st_ctime;
805 #if HAVE_STRUCT_STAT_ST_MTIMENSEC
806 			nsecs = st->st_ctimensec;
807 #endif
808 		}
809 #if HAVE_STRUCT_STAT_ST_BIRTHTIME
810 		/* FALLTHROUGH */
811 	case SHOW_st_btime:
812 		if (!gottime) {
813 			gottime = 1;
814 			secs = st->st_birthtime;
815 #if HAVE_STRUCT_STAT_ST_BIRTHTIMENSEC
816 			nsecs = st->st_birthtimensec;
817 #endif /* HAVE_STRUCT_STAT_ST_BIRTHTIMENSEC */
818 		}
819 #endif /* HAVE_STRUCT_STAT_ST_BIRTHTIME */
820 		small = (sizeof(secs) == 4);
821 		data = secs;
822 		sdata = fmttime(path, sizeof(path), timefmt, secs, nsecs);
823 
824 		formats = FMTF_DECIMAL | FMTF_OCTAL | FMTF_UNSIGNED | FMTF_HEX |
825 		    FMTF_FLOAT | FMTF_STRING;
826 		if (ofmt == 0)
827 			ofmt = FMTF_DECIMAL;
828 		break;
829 	case SHOW_st_size:
830 		small = (sizeof(st->st_size) == 4);
831 		data = st->st_size;
832 		sdata = NULL;
833 		formats = FMTF_DECIMAL | FMTF_OCTAL | FMTF_UNSIGNED | FMTF_HEX;
834 		if (ofmt == 0)
835 			ofmt = FMTF_UNSIGNED;
836 		switch (hilo) {
837 		case HIGH_PIECE:
838 			shift = 30;	/* gigabytes */
839 			hilo = 0;
840 			break;
841 		case MIDDLE_PIECE:
842 			shift = 20;	/* megabytes */
843 			hilo = 0;
844 			break;
845 		case LOW_PIECE:
846 			shift = 10;	/* kilobytes */
847 			hilo = 0;
848 			break;
849 		}
850 		break;
851 	case SHOW_st_blocks:
852 		small = (sizeof(st->st_blocks) == 4);
853 		data = st->st_blocks;
854 		sdata = NULL;
855 		formats = FMTF_DECIMAL | FMTF_OCTAL | FMTF_UNSIGNED | FMTF_HEX;
856 		if (ofmt == 0)
857 			ofmt = FMTF_UNSIGNED;
858 		break;
859 	case SHOW_st_blksize:
860 		small = (sizeof(st->st_blksize) == 4);
861 		data = st->st_blksize;
862 		sdata = NULL;
863 		formats = FMTF_DECIMAL | FMTF_OCTAL | FMTF_UNSIGNED | FMTF_HEX;
864 		if (ofmt == 0)
865 			ofmt = FMTF_UNSIGNED;
866 		break;
867 #if HAVE_STRUCT_STAT_ST_FLAGS
868 	case SHOW_st_flags:
869 		small = (sizeof(st->st_flags) == 4);
870 		data = st->st_flags;
871 		sdata = NULL;
872 		formats = FMTF_DECIMAL | FMTF_OCTAL | FMTF_UNSIGNED | FMTF_HEX;
873 		if (ofmt == 0)
874 			ofmt = FMTF_UNSIGNED;
875 		break;
876 #endif /* HAVE_STRUCT_STAT_ST_FLAGS */
877 #if HAVE_STRUCT_STAT_ST_GEN
878 	case SHOW_st_gen:
879 		small = (sizeof(st->st_gen) == 4);
880 		data = st->st_gen;
881 		sdata = NULL;
882 		formats = FMTF_DECIMAL | FMTF_OCTAL | FMTF_UNSIGNED | FMTF_HEX;
883 		if (ofmt == 0)
884 			ofmt = FMTF_UNSIGNED;
885 		break;
886 #endif /* HAVE_STRUCT_STAT_ST_GEN */
887 	case SHOW_realpath:
888 		small = 0;
889 		data = 0;
890 		if (file == NULL) {
891 			(void)strlcpy(path, "(stdin)", sizeof(path));
892 			sdata = path;
893 		} else {
894 			snprintf(path, sizeof(path), " -> ");
895 			if (realpath(file, path + 4) == NULL) {
896 				if (!quiet)
897 					warn("realpath `%s'", file);
898 				linkfail = 1;
899 				l = 0;
900 				path[0] = '\0';
901 			}
902 			sdata = path + (ofmt == FMTF_STRING ? 0 : 4);
903 			prefixlen = (ofmt == FMTF_STRING ? 4 : 0);
904 		}
905 
906 		formats = FMTF_STRING;
907 		if (ofmt == 0)
908 			ofmt = FMTF_STRING;
909 		break;
910 	case SHOW_symlink:
911 		small = 0;
912 		data = 0;
913 		if (S_ISLNK(st->st_mode)) {
914 			snprintf(path, sizeof(path), " -> ");
915 			l = readlink(file, path + 4, sizeof(path) - 4 - 1);
916 			if (l == -1) {
917 				if (!quiet)
918 					warn("readlink `%s'", file);
919 				linkfail = 1;
920 				l = 0;
921 				path[0] = '\0';
922 			}
923 			path[l + 4] = '\0';
924 			sdata = path + (ofmt == FMTF_STRING ? 0 : 4);
925 			prefixlen = (ofmt == FMTF_STRING ? 4 : 0);
926 		}
927 		else {
928 			linkfail = 1;
929 			sdata = "";
930 		}
931 		formats = FMTF_STRING;
932 		if (ofmt == 0)
933 			ofmt = FMTF_STRING;
934 		break;
935 	case SHOW_filetype:
936 		small = 0;
937 		data = 0;
938 		sdata = "";
939 		if (hilo == 0 || hilo == LOW_PIECE) {
940 			switch (st->st_mode & S_IFMT) {
941 			case S_IFIFO:	sdata = "|";			break;
942 			case S_IFDIR:	sdata = "/";			break;
943 			case S_IFREG:
944 				if (st->st_mode &
945 				    (S_IXUSR | S_IXGRP | S_IXOTH))
946 					sdata = "*";
947 				break;
948 			case S_IFLNK:	sdata = "@";			break;
949 #ifdef S_IFSOCK
950 			case S_IFSOCK:	sdata = "=";			break;
951 #endif
952 #ifdef S_IFWHT
953 			case S_IFWHT:	sdata = "%";			break;
954 #endif /* S_IFWHT */
955 #ifdef S_IFDOOR
956 			case S_IFDOOR:	sdata = ">";			break;
957 #endif /* S_IFDOOR */
958 			}
959 			hilo = 0;
960 		}
961 		else if (hilo == HIGH_PIECE) {
962 			switch (st->st_mode & S_IFMT) {
963 			case S_IFIFO:	sdata = "Fifo File";		break;
964 			case S_IFCHR:	sdata = "Character Device";	break;
965 			case S_IFDIR:	sdata = "Directory";		break;
966 			case S_IFBLK:	sdata = "Block Device";		break;
967 			case S_IFREG:	sdata = "Regular File";		break;
968 			case S_IFLNK:	sdata = "Symbolic Link";	break;
969 #ifdef S_IFSOCK
970 			case S_IFSOCK:	sdata = "Socket";		break;
971 #endif
972 #ifdef S_IFWHT
973 			case S_IFWHT:	sdata = "Whiteout File";	break;
974 #endif /* S_IFWHT */
975 #ifdef S_IFDOOR
976 			case S_IFDOOR:	sdata = "Door";			break;
977 #endif /* S_IFDOOR */
978 			default:	sdata = "???";			break;
979 			}
980 			hilo = 0;
981 		}
982 		formats = FMTF_STRING;
983 		if (ofmt == 0)
984 			ofmt = FMTF_STRING;
985 		break;
986 	case SHOW_filename:
987 		small = 0;
988 		data = 0;
989 		if (file == NULL) {
990 			(void)strlcpy(path, "(stdin)", sizeof(path));
991 			if (hilo == HIGH_PIECE || hilo == LOW_PIECE)
992 				hilo = 0;
993 		}
994 		else if (hilo == 0)
995 			(void)strlcpy(path, file, sizeof(path));
996 		else {
997 			char *s;
998 			(void)strlcpy(path, file, sizeof(path));
999 			s = strrchr(path, '/');
1000 			if (s != NULL) {
1001 				/* trim off trailing /'s */
1002 				while (s != path &&
1003 				    s[0] == '/' && s[1] == '\0')
1004 					*s-- = '\0';
1005 				s = strrchr(path, '/');
1006 			}
1007 			if (hilo == HIGH_PIECE) {
1008 				if (s == NULL)
1009 					(void)strlcpy(path, ".", sizeof(path));
1010 				else {
1011 					while (s != path && s[0] == '/')
1012 						*s-- = '\0';
1013 				}
1014 				hilo = 0;
1015 			}
1016 			else if (hilo == LOW_PIECE) {
1017 				if (s != NULL && s[1] != '\0')
1018 					(void)strlcpy(path, s + 1,
1019 						      sizeof(path));
1020 				hilo = 0;
1021 			}
1022 		}
1023 		sdata = path;
1024 		formats = FMTF_STRING;
1025 		if (ofmt == 0)
1026 			ofmt = FMTF_STRING;
1027 		break;
1028 	case SHOW_sizerdev:
1029 		if (S_ISCHR(st->st_mode) || S_ISBLK(st->st_mode)) {
1030 			char majdev[20], mindev[20];
1031 			int l1, l2;
1032 
1033 			l1 = format1(st,
1034 			    file,
1035 			    fmt, flen,
1036 			    majdev, sizeof(majdev),
1037 			    flags, size, prec,
1038 			    ofmt, HIGH_PIECE, SHOW_st_rdev, quiet);
1039 			l2 = format1(st,
1040 			    file,
1041 			    fmt, flen,
1042 			    mindev, sizeof(mindev),
1043 			    flags, size, prec,
1044 			    ofmt, LOW_PIECE, SHOW_st_rdev, quiet);
1045 			return (snprintf(buf, blen, "%.*s,%.*s",
1046 			    l1, majdev, l2, mindev));
1047 		}
1048 		else {
1049 			return (format1(st,
1050 			    file,
1051 			    fmt, flen,
1052 			    buf, blen,
1053 			    flags, size, prec,
1054 			    ofmt, 0, SHOW_st_size, quiet));
1055 		}
1056 		/*NOTREACHED*/
1057 	default:
1058 		errx(1, "%.*s: bad format", (int)flen, fmt);
1059 	}
1060 
1061 	/*
1062 	 * If a subdatum was specified but not supported, or an output
1063 	 * format was selected that is not supported, that's an error.
1064 	 */
1065 	if (hilo != 0 || (ofmt & formats) == 0)
1066 		errx(1, "%.*s: bad format", (int)flen, fmt);
1067 
1068 	/*
1069 	 * FLAG_POUND with FMTF_STRING means use vis(3) encoding.
1070 	 * First prefixlen chars are not encoded.
1071 	 */
1072 	if ((flags & FLAG_POUND) != 0 && ofmt == FMTF_STRING) {
1073 		flags &= !FLAG_POUND;
1074 		strncpy(visbuf, sdata, prefixlen);
1075 		/* Avoid GCC warnings. */
1076 		visbuf[prefixlen] = 0;
1077 		strnvis(visbuf + prefixlen, sizeof(visbuf) - prefixlen,
1078 		    sdata + prefixlen, VIS_WHITE | VIS_OCTAL | VIS_CSTYLE);
1079 		sdata = visbuf;
1080 	}
1081 
1082 	/*
1083 	 * Assemble the format string for passing to printf(3).
1084 	 */
1085 	lfmt[0] = '\0';
1086 	(void)strcat(lfmt, "%");
1087 	if (flags & FLAG_POUND)
1088 		(void)strcat(lfmt, "#");
1089 	if (flags & FLAG_SPACE)
1090 		(void)strcat(lfmt, " ");
1091 	if (flags & FLAG_PLUS)
1092 		(void)strcat(lfmt, "+");
1093 	if (flags & FLAG_MINUS)
1094 		(void)strcat(lfmt, "-");
1095 	if (flags & FLAG_ZERO)
1096 		(void)strcat(lfmt, "0");
1097 
1098 	/*
1099 	 * Only the timespecs support the FLOAT output format, and that
1100 	 * requires work that differs from the other formats.
1101 	 */
1102 	if (ofmt == FMTF_FLOAT) {
1103 		/*
1104 		 * Nothing after the decimal point, so just print seconds.
1105 		 */
1106 		if (prec == 0) {
1107 			if (size != -1) {
1108 				(void)snprintf(tmp, sizeof(tmp), "%d", size);
1109 				(void)strcat(lfmt, tmp);
1110 			}
1111 			(void)strcat(lfmt, "lld");
1112 			return (snprintf(buf, blen, lfmt,
1113 			    (long long)secs));
1114 		}
1115 
1116 		/*
1117 		 * Unspecified precision gets all the precision we have:
1118 		 * 9 digits.
1119 		 */
1120 		if (prec == -1)
1121 			prec = 9;
1122 
1123 		/*
1124 		 * Adjust the size for the decimal point and the digits
1125 		 * that will follow.
1126 		 */
1127 		size -= prec + 1;
1128 
1129 		/*
1130 		 * Any leftover size that's legitimate will be used.
1131 		 */
1132 		if (size > 0) {
1133 			(void)snprintf(tmp, sizeof(tmp), "%d", size);
1134 			(void)strcat(lfmt, tmp);
1135 		}
1136 		/* Seconds: time_t cast to long long. */
1137 		(void)strcat(lfmt, "lld");
1138 
1139 		/*
1140 		 * The stuff after the decimal point always needs zero
1141 		 * filling.
1142 		 */
1143 		(void)strcat(lfmt, ".%0");
1144 
1145 		/*
1146 		 * We can "print" at most nine digits of precision.  The
1147 		 * rest we will pad on at the end.
1148 		 *
1149 		 * Nanoseconds: long.
1150 		 */
1151 		(void)snprintf(tmp, sizeof(tmp), "%dld", prec > 9 ? 9 : prec);
1152 		(void)strcat(lfmt, tmp);
1153 
1154 		/*
1155 		 * For precision of less that nine digits, trim off the
1156 		 * less significant figures.
1157 		 */
1158 		for (; prec < 9; prec++)
1159 			nsecs /= 10;
1160 
1161 		/*
1162 		 * Use the format, and then tack on any zeroes that
1163 		 * might be required to make up the requested precision.
1164 		 */
1165 		l = snprintf(buf, blen, lfmt, (long long)secs, nsecs);
1166 		for (; prec > 9 && l < (int)blen; prec--, l++)
1167 			(void)strcat(buf, "0");
1168 		return (l);
1169 	}
1170 
1171 	/*
1172 	 * Add on size and precision, if specified, to the format.
1173 	 */
1174 	if (size != -1) {
1175 		(void)snprintf(tmp, sizeof(tmp), "%d", size);
1176 		(void)strcat(lfmt, tmp);
1177 	}
1178 	if (prec != -1) {
1179 		(void)snprintf(tmp, sizeof(tmp), ".%d", prec);
1180 		(void)strcat(lfmt, tmp);
1181 	}
1182 
1183 	/*
1184 	 * String output uses the temporary sdata.
1185 	 */
1186 	if (ofmt == FMTF_STRING) {
1187 		if (sdata == NULL)
1188 			errx(1, "%.*s: bad format", (int)flen, fmt);
1189 		(void)strcat(lfmt, "s");
1190 		return (snprintf(buf, blen, lfmt, sdata));
1191 	}
1192 
1193 	/*
1194 	 * Ensure that sign extension does not cause bad looking output
1195 	 * for some forms.
1196 	 */
1197 	if (small && ofmt != FMTF_DECIMAL)
1198 		data = (uint32_t)data;
1199 
1200 	/*
1201 	 * The four "numeric" output forms.
1202 	 */
1203 	(void)strcat(lfmt, "ll");
1204 	switch (ofmt) {
1205 	case FMTF_DECIMAL:	(void)strcat(lfmt, "d");	break;
1206 	case FMTF_OCTAL:	(void)strcat(lfmt, "o");	break;
1207 	case FMTF_UNSIGNED:	(void)strcat(lfmt, "u");	break;
1208 	case FMTF_HEX:		(void)strcat(lfmt, "x");	break;
1209 	}
1210 
1211 	/*
1212 	 * shift and round to nearest for kilobytes, megabytes,
1213 	 * gigabytes.
1214 	 */
1215 	if (shift > 0) {
1216 		data >>= (shift - 1);
1217 		data++;
1218 		data >>= 1;
1219 	}
1220 
1221 	return (snprintf(buf, blen, lfmt, data));
1222 }
1223